The Russian currency strengthened for seven straight weeks from early October to late November, rebounding from more than 100 to the dollar after President Vladimir Putin reintroduced capital controls mandating some exporters convert their FX revenues.
The rouble has since weakened to trade close to 93 per dollar now.
"The rouble's weakening at the start of December happened due to the seasonal decline of FX supply and the sustained volumes of FX purchases to pay for imports," the central bank said in a report.
The bank said Russians bought foreign currency worth 162.9 billion roubles ($1.77 billion) in November, mainly dollars and euros.
Finance Minister Anton Siluanov on Thursday said the capital controls were temporary.
"I am sure that the restrictions there are today will gradually go away," he said during the 'Russia Calling' financial forum in Moscow.
Central Bank Governor Elvira Nabiullina reiterated her opposition to the controls.
"I am a big opponent of the constant manipulation with currency restrictions," Nabiullina said. Repeated tweaks could lead businesses to try to preempt tighter restrictions and withdraw funds in advance, she added.
"This may additionally stimulate the outflow of capital," Nabiullina said. "They should be temporary."
The central bank last week said the measures would stay in place until the end of April.
($1 = 92.2850 roubles)
(Reporting by Elena Fabrichnaya and Alexander Marrow; Editing by Alison Williams and Barbara Lewis)
